Push rod tubes

[jolly500]

Hi,

I've got a 650cc motor with a skimmed head and am having a problem with the push rod tubes - the seals (thin type) seem to be pushing out at the bottom. I suppose logically the 'concertina' type would be better for my application as the compressibility should allow a better fit. Or maybe those fancy aluminium ones with the spring!

Anyone have any comments?

Thanks
Steve 

[Rusty's Uncle]

I thought that the solid tubes use the much deeper seals to take up the slack so if you have solid tubes & thin seals and they are being forced out then that sounds not good. I just happen to have some used concertina type tubes to hand and they measure 16cms shoulder to shoulder when not under load if that helps